Petkovic named 29 players for a preparatory camp in Bad Ragaz and has until Tuesday to cut the numbers down to 26 for the June 11 to July 11 tournament.
Petkovic said he was pleased with the way the new players had integrated into the squad.
The Czechs are in Group D along with Scotland, Croatia and England, playing their first two matches in Glasgow (June 14 and 18) before the final group game against England in London (June 22).
"The Czech national team will spend the whole UEFA Euro 2020 tournament in Prague instead of the base camp in Edinburgh as it was planned originally," the team said in a statement.
"The medical staff of the Dutch team are monitoring his condition closely and as soon as it is medical responsible, he will be drafted back into the squad," a statement from the Dutch football association said on Friday.
The Dutch fly to Portugal on Saturday without captain Georginio Wijnaldum and Frenkie de Jong, who are joining up with their teammates on Sunday.
He will succeed current coach Joachim Loew, with whom he won the World Cup as an assistant in 2014 and will have to complete an overhaul that was disrupted by a string of bad results and the coronavirus pandemic.
"Everything happened surprisingly quickly for me and I am happy to be national team coach from the autumn," Flick, who was the frontrunner for the post, said in a statement.
Gilmour and Turnbull will be joined by Manchester United's Scott McTominay in midfield, while both Liverpool's Andy Robertson and Arsenal's Kieran Tierney have been selected in defence.
Clarke named five forwards in his squad, including Celtic's James Forrest, who returns to the side for the first time since September having recovered from injury.
"It's never fun to lose matches, and in that moment it's extra disappointing when one doesn't contribute to the extent that one can because of injury, the body doesn't work - the disappointment is bigger, the frustration," the 26-year-old told Reuters.
"It's never fun to lose a final, so on Sunday I'm going to do all I can, because it's our turn to win."
The news led to calls from Serie A president Paolo Dal Pino for at least 1,000 fans to be allowed to attend league matches before the season ends in May.
Gravina said he was optimistic that fans would soon be allowed into stadiums after he had a meeting with the Undersecretary for Sport, Valentina Vezzali.
Abraham, 23, is Chelsea's top scorer this season with 12 goals in all competitions, but has found himself marginalised since the arrival of German coach Tuchel in January.
"I cannot make a decision on the personal goals of players," Tuchel told a news conference ahead of Saturday's Premier League game at Crystal Palace.
The Swede returned to his former club in January 2020 aged 38 and sparked a turnaround in form for the seven-time European champions, who have not won Serie A since 2011.
"Everyone knows him, his mentality - he's a winner," Bennacer told Reuters. "Maybe we didn't have this experience that he brought with him. It's good for us young players because we improved in this. Now we want to win like he wants to win.
"I'm sure that we will open the European Championship in Rome and that we will do it with a crowd in the stadium," Gravina told a news conference on Friday.
"I still don't know how many spectators there will be, but there will definitely be a crowd."
Loew is the current longest serving national team coach after taking the job in 2006 but the 61-year-old, who led Germany to the 2014 World Cup title, is ending his contract a year early.
"Will I be available for the German national team job in the summer? No," Klopp told reporters ahead of the second leg of their last-16 Champions League tie against RB Leipzig.
The 24-nation, month-long showpiece, a major revenue generator for the continent's soccer governing body UEFA and the national federations across Europe was postponed by 12 months.
We should not be dreaming," Blanc told Switzerland's 24 Heures newspaper. "In the best case it could be the second half of the year that we could lead a normal life again.